1. Field of the Invention
This invention relates to absorbent articles such as sanitary napkins, pantyliners, incontinent products or the like and, more particularly, relates to an individually wrapped absorbent article in which the article is releasably secured to a peel strip and folded and sealed to form a package. The package is wrapped and folded to form a pouch for storing and transporting the absorbent article. The invention additionally relates to a method of wrapping and folding an individually wrapped absorbent article of the aforementioned type and to an apparatus for practicing the method.
2. Discussion of the Related Art
Absorbent articles are well known for absorbing and retaining bodily fluids such as urine, menstrual fluids, blood, etc. Typical of these absorbent articles are sanitary napkins, pantyliners, incontinent products, and the like. The problems addressed by the art will be discussed primarily with reference to sanitary napkins, it being understood that pantyliners, incontinent products, and other absorbent articles also exhibit some or all of these problems.
The two types of sanitary napkins currently in use are a wingless or tabless type that is generally rectangular in shape and a winged or tabbed type that has wings or tabs (hereinafter xe2x80x9cwingsxe2x80x9d) extending laterally beyond the lateral edges of the main body of the napkin in a longitudinally central portion thereof. The typical sanitary napkin of either type comprises an absorbent core encased or enclosed within an envelope or sheath that includes a topsheet, also referred to as a xe2x80x9ccover,xe2x80x9d and a backsheet, also referred to as a xe2x80x9cbaffle.xe2x80x9d The topsheet is designed to face the user and is liquid-permeable to permit liquid passage to the absorbent core where the liquid is retained. The backsheet is liquid-impermeable. A strip of garment-attachable adhesive is secured on the outer surface of the backsheet to permit releasable or detachable securement of the napkin to a user""s undergarment. In the case of a winged or tabbed type napkin, additional adhesive strips or patches are secured to the bottom surface of the wings to permit securement of these wings to the user""s undergarment. The adhesive strips can be transferred to the napkins by applying the adhesive to the releasable peel strips, and the adhesive is then transferred to the napkins when the peel strip is attached to the backsheet or baffle. The peel strip protects the adhesive from contamination until the napkins are ready for use, at which time the user removes the peel strips.
Individually wrapped sanitary napkins are desirable for a variety of reasons. For instance, they are compact (e.g., they can be conveniently carried in a consumer""s pocket or purse), they prevent the sanitary napkins and the liners from becoming contaminated or soiled prior to use, and used napkins can be disposed of using the pouches or other wrapping materials. Individually wrapped sanitary napkins are disclosed, for example, in U.S. Pat. No. 3,973,567 to Srinivasan et al. (the Srinivasan patent); U.S. Pat. No. 4,556,146 to Swanson et al. (the Swanson patent); and U.S. Pat. No. 5,413,568 to Roach et al. (the Roach patent). All of these patents disclose a sanitary napkin having a backsheet portion adhered to a liner or peel strip that also forms at least part of a wrapper for the napkin. The Srinivasan and Swanson patents disclose individually wrapped wingless or tabless disposable sanitary napkins, whereas the Roach patent discloses an individually wrapped winged or tabbed sanitary napkin.
Conventional individually wrapped sanitary napkins such as those disclosed in the Srinivasan, Swanson, and Roach patents exhibit several drawbacks and disadvantages. For instance, they are relatively difficult to open. In the case of the Swanson patent, the wrapper faces and receives the backsheet portion of the napkin so as to present longitudinal and lateral flaps surrounding the napkin. The napkin and affixed wrapper are then tri-folded as a unit. The lateral edges of the longitudinal flaps are frangibly sealed along their entire length to prevent napkin contamination. These seals must be broken when unwrapping the assembly. This seal breaking requirement hinders unwrapping. In addition, the wrapper is ill-suited for disposal of a used napkin because it is not substantially larger than the napkin.
Napkins of the tabbed or winged type also exhibit additional wrapping challenges. For instance, in the Roach patent, a tabbed or winged type napkin is disclosed which has a backsheet that is releasably adhered to a wrapper similar to the manner in which the Swanson""s backsheet is adhered to the corresponding wrapper. However, the ends of the wings extend beyond the lateral edges of the wrapper. The exposed wings are folded longitudinally over the topsheet of the body of the napkin so that the wings are aligned and adjacent to the topsheet of the napkin with their ends facing the longitudinal centerline of the napkin and with their adhesive patches or strips facing upwardly. The wings must be covered with at least one and possibly two separate or dedicated pieces of release liner to protect the adhesive patches on the wings. The additional release liner(s) must be individually removed by the consumer prior to napkin use. This extra step is inconvenient at best and also presents the consumer with at least one additional piece of waste material for disposal. Moreover, because the wrapper is not substantially wider than the body of the napkin, it is rather difficult for the consumer to use the wrapper to dispose of a used napkin.
Another problem associated with conventional individually wrapped sanitary napkins is that production is hindered because wrapping and folding requires a separate process and apparatus and/or because the wrapping and folding operations cannot be performed in-line. Wrapping and folding instead are performed via rather large and complex drum, roll, and striker blade configurations that require at least one and usually several changes in the direction of napkin conveyance during the wrapping and folding processes. Examples of typical processes exhibiting these disadvantages can be found in U.S. Pat. No. 3,635,462 to Joa; U.S. Pat. No. 4,701,156 to Larsonneur; and U.S. Pat. No. 5,176,615 to Munsch.
It is therefore a principal object of this invention to provide an improved individually wrapped absorbent article that is compact and easy to unwrap.
Another object of this invention is to provide an absorbent article that meets the first principal object of this invention and that, in its fully wrapped state, is sanitary but still easy to unwrap.
Still another object of this invention is to provide an individually wrapped absorbent article that meets at least the first principal object and that does not require a separate peel strip as well as a wrapper.
Yet another object of this invention is to provide an individually wrapped absorbent article that meets at least the first principal object and that can be easily disposed of using the supplied wrapper.
In accordance with a first aspect of this invention, these objects are achieved by providing an individually wrapped absorbent article containing package that comprises an absorbent article and a wrapper. The absorbent article has first and second major mutually opposed faces, and the wrapper has an absorbent article-receiving surface to which at least a portion of the first face of the absorbent article is releasably secured to form an assembly. The assembly has a longitudinal centerline, a lateral centerline, and a perimeter. The perimeter is formed from a pair of opposed lateral edges disposed on opposite sides of the longitudinal centerline and a pair of opposed longitudinal ends disposed on opposite sides of the lateral centerline. The lateral edges are wrapped over the second face of the absorbent article and sealed to form a package.
Preferably, in order to fully-seal the package, a pair of opposed longitudinal ends of the package are each sealed by binding the wrapper to itself.
This invention is applicable to both winged absorbent articles such as winged sanitary napkins and the like and to wingless or tabless absorbent articles such as wingless sanitary napkins, pantyliners, and the like.
Another object of this invention is to provide a package which meets one or more of the foregoing objects and which is folded, rolled, or otherwise manipulated to form a pouch. Preferably, the pouch includes a central portion and first and second longitudinal flaps. The first longitudinal flap is aligned and adjacent to the central portion, and the second longitudinal flap is aligned and adjacent to the first longitudinal flap. The second longitudinal flap preferably is releasably secured to the first longitudinal flap.
Another principal object of this invention is to prove an individually-wrapped winged sanitary napkin that does not require separate peel strips for the wings of the napkin.
In accordance with another aspect of this invention, this object is achieved by providing an assembly formed from an absorbent article and a wrapper. The absorbent article has first and second major mutually opposed faces, includes a main absorbent body having opposed lateral edges, and includes a pair of wings extending laterally outward from the opposed lateral edges. At least a portion of the first face of the absorbent article is releasably secured to an article-receiving face of the wrapper to form the assembly. In order to protect the garment adhesive on the wings while eliminating the need for a separate peel strip on the wings, the portion of the first face that is secured to the wrapper includes at least part of the absorbent body and at least part of each of the wings.
Preferably, the assembly is wrapped to form a package and then folded to form a pouch as discussed above in conjunction with the first primary object.
Another principal object of this invention is to provide a relatively simple and expedient method of wrapping and folding an assembly formed from an absorbent article and a wrapper to which the absorbent article is releasably secured.
Preferably, the assembly has a longitudinal centerline and a perimeter formed from a pair of laterally-opposed side flaps disposed on opposite sides of the longitudinal centerline and a pair of opposed longitudinal ends. This assembly is wrapped and folded to form a pouch by folding the side flaps longitudinally onto the second face of the absorbent article to form a package, and then folding the package laterally to form a pouch. The step of folding the package laterally preferably comprises folding a first longitudinal flap of the package over a central portion of the package so that the first longitudinal flap is aligned and adjacent to the central portion, then folding a second longitudinal flap over the first longitudinal flap so that the second longitudinal flap is aligned and adjacent to the first longitudinal flap. The first and second longitudinal flaps are then releasably secured to one another.
Another object of this invention is to provide a method which meets the second principal object of this invention and which wraps and folds the absorbent articles in an in-line fashion.
In accordance with still another aspect of this invention, this object is achieved by driving a first reciprocating pusher into the package at a location in the vicinity of a lateral fold-line connecting the central portion to the first longitudinal flap, and by driving a second reciprocating pusher into the package at a location in the vicinity of a lateral fold-line connecting the central portion to the second longitudinal flap.
Yet another principal object of this invention is to provide an improved system for wrapping and folding individually wrapped absorbent articles.
In accordance with still another aspect of this invention, this object is achieved by providing a first conveyor which is adapted to convey assemblies comprising a wrapper and an absorbent article secured to the wrapper to the system, a second conveyor which is adapted to convey pouches from the system, and first and second pusher assemblies. The first pusher assembly comprises a vertically reciprocating pusher which is adapted to receive the assemblies from the first conveyor and to partially-fold the assemblies. The second pusher assembly is a horizontally reciprocating pusher located in a vertically-spaced relationship with respect to the first conveyor and the first pusher and which is adapted to receive the assemblies from the first pusher and to further fold the assemblies to form the pouches.
Preferably, the first and second pushers are slotted to permit application of an adhesive to the assemblies without interference from the first and second pushers.
Other system components preferably include 1) a package former which releasably secures absorbent articles to a continuous sheet of wrapper material to form the packages, 2) a longitudinal folder which is located downstream of the package former and which folds the continuous sheet longitudinally to form wrapped packages in which lateral edges of the continuous sheet are positioned laterally inwardly of lateral edges of the packages, and 3) a cutter which is located between the longitudinal folder and the first conveyor and which cuts the continuous sheet between the packages.
Other objects, features, and advantages of the present invention will become apparent to those skilled in the art from the following section entitled Detailed Description of the Preferred Embodiment and from the accompanying drawings. It should be understood, however, that the Detailed Description and specific drawings, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.